Air brake mechanism for pilger mill feed gears



H. DREYER 1,833,990

AIR BRAKE MECHANISM FOR PILGER MILL FEED GEARS Filed March 16, 1928 WITNESS O/MMZQM- nansnnn nn; or p V 'ens Lrsown-or nussELnoRneEm/rm- Patented Dec. 1, 1931' nu'ssnnnonr, GERMANY, ASSIGNOR 'ro scmmam Am 3 mm MncH nIsil! FOR mam MILL FEED ennn's Application filed March 16,1928, Serial No.

In iada a pmas for pilger mills an important element is the braking andtaking up of the shock due to the moving massJof the mechanism including a blank in the form; of a pierced billet or a hollow bloom, a mandrel bar, coupling box, rod, etc," which mass is moved forwardly at a high velocit to bring the blank into the bite of a pair 0 swaging rolls. Liquid or air in combinationiwitzh va-; rious mechanical means have been used for such braking; With liquid-operated brakes, the throttling, that-is, the absorption of the stored-up energy, causes the liquid in time to become veryhot, requiring the provision of special cooling means. In air-operated brakes, the rapid compression of the air causes it and the walls of its container to be-' come highly heated. The compressedheated air is either allowed to escape to the atmos phere, or is returned throu h pipes to the compressed air cylinder whic provides driving power for the forward movement of the reciprocating parts of the feeding mecha nism; The brake compression, which gradu ally becomes hotter-and the dimensions of which .are fixed, causes the air flowing in it to immediately become heated andtoac cordingly expand and add additional pressure. ecause of this heating, the specific gravity of the air becomes less and less, and the weight of the air to be compressed continues to decrease, so that the distance through which the brake acts also becomes shorter and shorter with the compression pressure greater than originally intended.

Hence, irrespective of the air loss through the adjustment of the braking path, thequantities of air for the compression work must be continuously varied to correspond with varying temperatures.

The object of the invention is to provide a brake for a pilger mill feeding apparatus which is simple and efl'ective in construction I and which overcomes the prejudicial features incident to the use of the fluid brakes heretofore used.

The invention is illustrated in the accompanying drawing which is a vertical central longitudinal sectionthrough a pair of pilger 262,262, and m German-y ltarch 18,?1927;

millswagi-ng rolls feed apparatus asso:

ciatedwith them. 1

vAccording to this-invention asuitable part of'the reciprocating portion'of a feed apparatus for a pilgermill is utilizedas a brake piston rod and is surrounded by a brakecylin der, adapted to contain a body of liquid. Above, and in free communication with this cylinder there is a closed reservoir, thelower portion of which andthe cylinder are pro-;

vided with a body ofliquid, Air, or any othor suitablelgas, occupies the space above the liquid; in the reservoir. The piston, rod, which reciprocatesthrough they liquid+cor taining cylinder, is provided with apiston so constructed and positioned that on the for-i ward feeding'stroke of the piston, the liquid, or. a, portion oi it, in the cylinder, isdriven into the reservoir against the compression re:

slst'ance of the a1r 1n itsv upper portion which affordseffective braking resistance to the for ward movement of the moving mass. -Thc heatdeveloped consequent upon this compressionof the air ,is-a bsorbed by, the upper por tion-ofthe liquid and the wall of the reser voir, and becomes dissipated on the rearward movement of the feed mechanism, during" which movement the compressed air acts through the liquid and on the piston the feed mechanism rea'rwardly'. w .1 Having reference new to the illustrative, embodiment ofthe invention, there is shown a pairof swaging rolls 1 of familiar construction, the rolls being indicated as acting upon a blank 2 supported by a mandrel bar 3, suitably attached bya couplingbox 4 to. the end of a rod 5. forming part of. the feed mechanismi. While any. suitable motivepower may be usedfor' moving rod fiandi its attachedlmandrel forwardly, this is prefere ably done'by compressed air; 1 To such end, 7 "the rear portion of rod-5 .is' connected to a tubular rodt of larger diam eter'than rod i5f, rod ,6 being'provided' withi apisto'n 7 which operates in a c mpressed air cylinder'S.

Rearwardlyfof piston 7,there isja twist nut 9 which receives a suitablythreaded spindle'10 attached to: the piston. For turriingrthe to, urge twist nut throughv an angle 0&90 at the propl er time during eaclrcycleof operation ofthe swage rolls as is commonly done iii pilger mills, the outer end jof the nut is attached to asuitable turning mechanism 11 which may Y be of any desired type of construction.

Compressed air cylinder 8, and also the brake mechanism about toibe' -desc-ribed,"- are, attached to a carrier 12 which is slidably mounted upon a suitable frame 13,:the d e-ii tailed construction of which together vwith the mechanism for moving carrier 12 for-.

, wardly increment bv increment being Well known iii this art, and accordingly not-illustrated.

Surrounding rod 5 there is a cylinder. 15

provided at its forward end with a packing gland 16 through which the rod reciprocates, and at its rear end with a similar gland 17 through which the forward end of tubular rod 6ireciprocatess By this construction the enlargement formed at the point of connection of rod 5 and tube .6 forms a: piston18 in cylinder 151- Attachedf'to cylinder 15', and projecting above it, there is a reservoir 19in free communication withthe cylinder. As indicated on the drawing, cylinder 15 and the lower portionof reservoir 19, is provided with a body of liquid 20 whichis preferablyoil,

the space21 abovethe oil inthere'servoir being filled with" air. To vary the relative pr0- portions of air and liquid in the I'GSQIVOlPfOl the purpose presently tobe 'explained,the

reservoir is provided with" a valve controlled air passage 22 and a valve controlled liquid 7 'airbecomes compressed; When the ends 25 T of the enlarged portions of rolls 1 move from engagement with blank 2 the compressed air incylinder 8 at the rear of piston 7 exerts the sole brake for said mechanism.

vupon piston 18 to urge the mechanism rearward.

According to the provisions of the patent statutes, I have explained the principle of 2 my invention, and have illustrated and de- 7 scribed what I now consider to represent its best improvement. However, If desire to have it understood that, within the scope of the, appendedclaims, the invention may be practiced by other'forms of construction than specifically illustrated and described.

"I claim asmy invention 1. A feed apparatus bra p'ilger mill, comprising a cylinder, mandrel-carrying mechanism including a rod reciprocable through and provided with a piston within said cylinder, and a'closed reservoir above and having free liq-uidfflowing communication with said cyl nder, said cylinder and'the lower-portion of theireservoir being providedwith a body of liquid which freely flowsto and "from the cylinder and reservoir during the entire reciprocatioii ofsaid piston,"and the upper por tion of the reservoir 'containingair forming "2. A teed apparatus for a pilger mill, coins prising a cylinder,mandrel-carryingme-chanism including a rod reciprocablethrough and provided with a piston withinsaidcylin; der, ,a'closed reservoir: above and having free liquid-flowing communication with said cylinder, said-cylinder andthe lower portion of thezreservoir being provided with a, body of liquid which freely flows to and-from the cylinder and reservoir during the entire reciprocation of said piston, and the upper. portion of the reservoir containing air form ing-the sole; brake'for said mechanism, and nieaiisfor'varyingtlie relative proportions of braking resistance; r In testimony-whereof,

name.-

its pressure to thrust forwardly the movable parts of the feed mechanism-just explained.

During this forward movement, piston 18 on-rod 5 forces the liqu'id,or a portion of it, from cylinder 15 into reservoir 19 which resultsin compressing the airin the upper portion of the reservoir. Resistance to this compression of the air in thereserv'oir affords an effective brake resistance to the forward movement of the movable parts of the feed mechanism, which resistance may be varied V to meet diflerent requirements'ofser vicqrby varying the relative amounts of air and liquid in the reservoir-through valve controlled HANS DREYER'. A

lhereunto sign my passages 22' and 23. On' the rearward movement oi the feed mechanism, the compressed air in the. upperportionof reservoir a acts *throughthe may of liquid 20 and V air and liquid inflsaid reservoir to vary the 

